[SOLVED] CB / Joomla authentication from SmartPhone App

Forgive if this is obvious...but if I was building an iOS / Android app and wanted that app to be able to authenticate as per the CB user's app settings....what is the best method?
Any code snippets to get me going?
Fairly new to Joomla / CB but if you point me in the right direction, just might be able to figure it out

TIA.

Found a plugin... www.textarea.it/joomla-extensions/joomla-autologin.html
should do the trick.